Description ADULT MALE In winter, has pure white plumage with black eye and dainty bill. In summer, has barred and marbled brown and yellow-buff upperparts with black feathering on flanks and breast. Underparts are mainly white. ADULT FEMALE In winter is pure white and similar to male. In summer, similar to male, but with less white on underparts. JUVENILE Similar to summer female.

Discussion Hardy, plump-bodied ptarmigan; the smallest of its kind in North America. White tail is diagnostic at all times (Rock and Willow have black tail feathers). Usually solitary during breeding season, but forms small flocks at other times. Feeds on seeds, shoots, and stems.